Writing instrument



FIG. 1 is a top, side and back perspective view of an embodiment of the present invention;

FIG. 2 is a side view of the pen embodied in FIG. 1;

FIG. 3 is a front view of the pen in the FIG. 1 embodiment;

FIG. 4 is a bottom view of the pen illustrated in FIG. 1; and,

FIG. 5 is a top, side, back perspective view of a second embodiment of the concept of the present invention. 

The ornamental design for a writing instrument, as shown and described. 